Method for fabricating a needle assembly

ABSTRACT

Methods and apparatuses for fabricating a needle assembly which includes a blunt in a cannula of a needle. In one example of a method, at least one blunt is collected in a cutout of a blade from a set of blunts and a fluid is passed across said cutout. Any further blunts around the cutout are dislodged by the fluid, leaving only one blunt on the blade. In another example of a method, a blade is moved to a first position to collect at least one blunt from a set of blunts, and the blade is moved to a second position to singulate the one blunt from the set of blunts; the blade has a tip end which is designed to capture securely only one blunt, wherein any further blunts are not securely maintained in the tip end. An exemplary apparatus includes a container for holding a set of blunts, a motor, and a blade coupled to the motor and disposed at least partially within a slot of said container. The blade includes a tip end which is designed to capture securely only one blunt.

BACKGROUND OF THE INVENTION

The present invention relates to methods and apparatuses for fabricatingan assembly which includes a blunt and, in one particular embodiment,relates to an apparatus for fabricating a needle assembly which includesa blunt.

The present invention relates to medical devices and other similardevices and in particular to medical devices such as intravenouscatheters and syringes which include a hollow needle having a sharpdistal end for piercing an object, such as the skin of a patient.

The existence of infectious diseases has highlighted the danger to whichmedical personnel may be exposed when treating patients by means ofcatheter devices and syringes where a sharp needle point is used topierce the skin of the patient. In order to protect medical personnelagainst inadvertent needle stick, a number of solutions have beendeveloped whereby a protective mechanism, incorporated within a catheteror syringe, prevents physical contact with the sharp needle point afteruse and hence protects against inadvertent needle stick. One suchsolution which has been developed is the use of a blunt which iscontained within the cannula of the hollow needle. An example of a bluntis described in co-pending U.S. patent application Ser. No. 09/221,272,which was filed Dec. 23, 1998, by the inventors Joseph, Chang, PhilipSchmidt, and Dennis Bialecki and which is entitled “Solid Blunt for aNeedle Assembly.” One example of a blunt described in this patentapplication is a blunt having a substantially D-shaped cross-section. Inmass production, this blunt would typically be manufactured in largenumbers before being inserted into the cannula of a needle in order tocreate the final product. Current manufacturing techniques for producingneedle assemblies often include the use of a blade-style feeder whichsingulates a needle from a collection of needles in order to assemblethe needle with the rest of the assembly which makes up the needleassembly. FIG. 1 shows an example of a process for singulating a needlefrom a collection of needles in order to fabricate a needle assembly byconnecting the needle to a hub, etc. The feeder 101 is shown in FIG. 1in cross-sectional view. The feeder includes a container 103 which has awall 109 which supports a plurality of needles 107 such as needles 107a, 107 b, 107 c, and 107 d. A blade-style feeder 105 is disposed withina slot 111 of the container 103. The blade 105 is coupled to a motor 112which drives the blade up and down as shown by the arrow 114. When theblade 105 is driven down such that the top surface of the tip 105 a isapproximately at the position 105 b as shown in FIG. 1, then one needlewill tumble into the cutout of the tip 105 a. As the blade 105 is pushedup away from the wall 109 to the position shown in FIG. 1, only oneneedle will remain in the tip 105 a as any other needles will tumble offof the top of the tip 105 a. This causes a single needle to be selectedin a singulation process from the set of needles held in the container103.

It is desirable in the manufacturing process for needle assemblies whichinclude blunts to use a similar blade-style feeder to singulate a bluntfrom a set of blunts in order to take the singulated blunt and theninsert it into the cannula of a needle to assemble the needle assembly.A D-shaped blunt presents a challenge for the blade-style feeder shownin FIG. 1. This challenge is shown in FIGS. 2A and 2B which show thatthe blade 105 may not successfully singulate one blunt from a collectionof blunts. As shown in FIG. 2A, which is a cross-sectional view, twoD-shaped blunts 203 and 205 may be stably maintained on the cutout ofthe tip 105 a. In this case, it may be impossible to singulate one bluntfrom a group of blunts. Similarly, as shown in FIG. 2B which is across-sectional view, two blunts 207 and 209 may remain stably held inthe cutout of the tip 105 a when the blunts stack vertically as shown inFIG. 2B.

While it is desirable to use a feeder to singulate blunts in the samemanner that a feeder is used to singulate needles, the currentlyexisting blades do not provide adequate performance in singulatingblunts.

From the above discussion, it can be seen that it is desirable toprovide an improved method and apparatus for singulating a blunt in theprocess of fabricating a needle assembly or for fabricating otherassemblies which use a blunt.

SUMMARY OF THE INVENTION

The present invention provides a method of fabricating an assembly whichincludes a blunt, and also provides an apparatus for fabricating anassembly which includes a blunt.

In one exemplary embodiment, a method of the invention includescollecting from a set of blunts at least one blunt in a blade having acutout and passing a fluid past the cutout. In another example accordingto the present invention, the method includes moving a blade to a firstposition to collect at least one blunt from a set of blunts and movingthe blade to a second position to singulate the one blunt from the setof blunts, where the blade has a tip end which is designed to capturesecurely only the one blunt and wherein any further blunts are notsecurely maintained in the tip end.

An apparatus in another exemplary embodiment includes a container forholding a set of blunts and includes a motor. A blade, which is disposedat least partially within a slot of the container and which is coupledto the motor, has a tip end which is designed to capture securely onlyone blunt, wherein any further blunts are not securely maintained in thetip end.

The present invention may be used to fabricate medical devices,including needles, syringes, catheter assemblies and introducers forcatheters as well as other devices which include a blunt.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and notlimitation in the figures of the accompanying drawings in which likereferences indicate similar elements.

FIG. 1 shows a cross-sectional view of a prior art system forsingulating one hollow needle shaft from a group of hollow needleshafts.

FIG. 2A shows an example of the use of the blade-style feeder from FIG.1 in a system which is attempting to singulate a D-shaped blunt.

FIG. 2B shows another example of the blade-style feeder from FIG. 1 andits attempt to singulate two D-shaped blunts.

FIG. 3 is a flowchart which shows a sequence of operations in amanufacturing process for assembling a blunt into the cannula of aneedle in order to fabricate a medical device such as a syringe or acatheter introducer.

FIG. 4A shows a cross-sectional view of a blade feeder according to oneembodiment of the present invention.

FIG. 4B shows a side view of a blade feeder according to one embodimentof the present invention.

FIG. 5 illustrates the use of a blade according to the present inventionin an apparatus according to the present invention which may be used tosingulate D-shaped blades.

FIGS. 6A, 6B, and 6C are cross-sectional views showing various examplesof how the blade of the present invention, according to one embodiment,will successfully singulate a blade from a group of blades.

DETAILED DESCRIPTION

The present invention provides various examples of methods andapparatuses for fabricating an assembly which includes a blunt. Thefollowing description and drawings are illustrative of the invention andare not to be construed as limiting the invention. Numerous specificdetails are described to provide a thorough understanding of theinvention. For example, very specific geometries and dimensions areprovided for purposes of illustrating the invention. In certaininstances, well known or conventional details are not described in orderto not unnecessarily obscure the present invention in detail.

At least one embodiment of the present invention allows the utilizationof familiar feeding technology in order to singulate both the needlesand the blunts to provide a single needle which then may be mated with asingle blunt. This is particularly desirable when the manufacturingassembly process requires that the D-shaped blunt in one embodiment besingulated before being bonded to the needle's hub or other componentsin the assembly. FIG. 3 shows an example of the flow of operations in amanufacturing assembly process according to one embodiment of theinvention. Operation 301 involves the fabrication of the needles(referred to as cannulas here). The needles are collected on a firstcontainer. In operation 303, the blunts are fabricated and collected ina second container. Then in operation 305, a single needle is selectedfrom the collection of needles in the first container. Similarly, inoperation 307, a single blunt is selected from the collection of bluntsin the second container. Then in operation 309, the single bluntsingulated in operation 307 is assembled with the single needlesingulated in operation 305. In operation 311, the fabrication processis completed to complete the final product, such as a catheterintroducer or a syringe. It will be appreciated that several of thesteps may be performed in a different order or concurrently. However, itis desirable in this embodiment to singulate the needle and the bluntprior to their assembly in operation 309. The present inventionprovides, in at least one embodiment, a method and apparatus forsingulating a blunt which has a D-shaped geometry or other geometrieswhich may make it difficult to singulate a blunt from a group of blunts.

FIG. 4A shows a cross-sectional view of one example of a blade feeder ofthe present invention. In this cross-sectional view, the blade 401includes a main body which has a tip end 402 which includes a cutout403. The cutout 403 is designed to have a geometry, relative to thegeometry of the cross-section of the blunt, so that only one blunt issecurely maintained in the cutout and any further blunts will not besecurely maintained within the cutout. FIG. 4A shows various dimensionsand angles for a particular embodiment of a blade feeder of theinvention. This figure and the following table provide very specificexamples for dimensions of certain feeders. In particular, in Table Abelow, specific examples for particular dimensions of the feeder arespecified relative to certain D-shaped blunts of specified gauge sizes.The dimension A shown in FIG. 4A corresponds to A in the table, and thedimension B shown in Table A corresponds to the dimension B shown inFIG. 4A. The dimensions shown in FIG. 4A are in inches.

TABLE A Gauge Dim “A” ± Dim “B” ± Size .001 .001 14 gauge .050 .034 16gauge .037 .026 18 gauge .030 .020 20 gauge .022 .015 22 gauge .016 .01124 gauge .013 .009

The gauge size in Table A represents the gauge size of the D-shapedblunt. It can be seen that in this particular embodiment, the geometryof the tip end of the blade consists of a quarter-pie-shaped profilewhere one portion of the profile is higher than the other. This higherportion of the profile provides protection for a single blunt from anair jet which is used in one embodiment as described below. Thedimensions shown in the table are in inches.

FIG. 4B shows a side view of the blade according to one exemplaryembodiment of the invention. The blade 401 includes a tip end 402 andalso includes another end where several cutouts 405, 406, 407, and 408are located. These cutouts may be used to couple the blade to the motorwhich drives the blade up and down within the assembly, such as themotor 112 of FIG. 5 which will be described below. The tip end alsoincludes a cutout 409. The cutout 409 is used, in conjunction with agripper, to remove a singulated blunt from the blade.

FIG. 5 shows a cross-sectional view of an apparatus according to oneexemplary embodiment of the invention. The apparatus 501 includes acontainer 103 which holds a collection of blunts along the wall 109 ofthe container. The collection of blunts 509 will be singulated by theblade 401. The blade 401 is coupled to the motor 112 which causes theblade 401 to move up and down within the slot 111 of the container 103along the vertical arrow 114 as shown in FIG. 5. The reciprocating upand down motion of the blade 401 causes the blade's cutout 403 tosecurely select only one D-shaped blunt from the collection of blunts509.

One particular embodiment of the present invention may utilize a fluid,such as a pressurized air stream, which is pulsed to provide a jet ofair when the blade 401 reaches its uppermost position in its travel upand down. The jet of air 505 may be emitted from a nozzle 503 which ispositioned to direct the stream of air at approximately the locationthat the tip 402 will be in when the blade 401 is near its uppermosttrajectory in its up and down travel. Alternatively, the air jet may bemaintained on a constant on state or the air jet may be turned on when asensor detects more than one blunt in the blade cutout 403. The sensormay be an automatic sensor such as a light-detecting sensor (e.g. a beamof light is projected across the top of the tip and can only beinterrupted when more than one blunt is present in the cutout and whenthe blade is at its uppermost position).

FIGS. 6A, 6B and 6C show various examples of how more than one D-shapedblunt can be picked up by the blade 401 in the cutout 403. However, ineach case, the second blunt is significantly exposed and will not bemaintained on the tip end of the blunt after the air jet is pulsed toremove the second blunt.

It will be appreciated that other blunt shapes may be accommodated inthe blade by altering the shape of the cutout in the tip end of theblade. The shape of the cutout should be designed to securely hold onlyone blunt and to leave any other blunts not securely maintained so thatan air jet, if used, may remove the second blunt. In another alternativeembodiment, the blade may be vibrated to knock off an extra blunt.

In the foregoing specification, the invention has been described withreference to specific exemplary embodiments thereof. It will be evidentthat various modifications may be made thereto without departing fromthe broader spirit and scope of the invention as set forth in thefollowing claims. The specification and drawings are, accordingly, to beregarded in an illustrative sense rather than a restrictive sense.

What is claimed is:
 1. A method of separating a blunt from a set of blunts useable as part of a process to fabricate an assembly, said method comprising: fabricating a set of needles; collecting, from said set of needles, at least one needle; fabricating said set of blunts; collecting, from said set of blunts, at least one blunt in a blade having a cutout; passing a fluid past said cutout to remove all but said at least one blunt from said cutout; and assembling said at least one blunt with said at least one needle.
 2. A method as in claim 1 further comprising: designing said set of blunts to provide needle stick prevention; and designing said set of blunts to extend from beyond a distal end of said needle after said needle is used.
 3. A method as in claim 2, said method further comprising: moving said blade in a predetermined fashion to perform said collecting.
 4. A method as in claim 3 further comprising: configuring said predetermined fashion such that said blade moves in an up and down motion.
 5. A method as in claim 4 wherein said method further comprises: dispensing said set of blunts into a container, and wherein said blade is disposed in a slot in a wall of said container and said blade moves up and down in said slot.
 6. A method as in claim 1 further comprising configuring said passing a fluid to include pressurized air which is directed in a stream toward said cutout.
 7. A method as in claim 4 further comprising directing said passing a fluid at said cutout when said blade is up.
 8. A method as in claim 4 further comprising directing said passing a fluid toward said cutout when more than said at least one blunt is detected in said cutout.
 9. A method as in claim 1 further comprising: mounting said at least one blunt into said at least one needle.
 10. A method for separating a blunt from a set of blunts useable as part of a process to fabricate an assembly, said method comprising: fabricating a set of needles; collecting, from said set of needles, at least one needle; fabricating said set of blunts; moving a blade to a first position to collect at least one blunt from said set of blunts; moving said blade to a second position to singulate said at least one blunt from said set of blunts, said blade having a tip end which is designed to capture securely only one said blunt at a time, wherein in an event that a further blunt couples to said tip end at said time, said further blunt is not securely maintained in said tip end at said time; passing a fluid over said tip end, said passing a fluid dislodges said further blunt from said tip end in the event that said further blunt couples to said tip end; and assembling said at least one blunt with said at least one needle. 